Printed circuit boards with electrical contacts and solder joints of higher melting temperatures

Abstract

A chip may be secured to a first printed circuit board (PCB) via a first solder joint. The first PCB may be secured to a second PCB via a second solder joint. The melting temperature of the first solder joint may be higher than the melting temperature of the second solder joint.

What is claimed is: 
     
         1 . An apparatus comprising:
 a first printed circuit board (PCB);   a first electrical contact on a first surface of the first PCB; and   a second electrical contact on a second surface of the first PCB, the second surface opposite the first surface, the second electrical contact coupled to the first electrical contact;   a first solder joint to secure a chip to the first PCB at the first electrical contact; and   a second solder joint to secure the first PCB to a second PCB at the second electrical contact, wherein a melting temperature of the first solder joint is higher than a melting temperature of the second solder joint.   
     
     
         2 . The apparatus of  claim 1  comprising a processor socket, the chip secured to the processor socket, and the processor socket secured to the first PCB at the first electrical contact via the first solder joint. 
     
     
         3 . The apparatus of  claim 1 , the first PCB comprising a heater trace to heat the second solder joint to be greater than or equal to the melting temperature of the second solder joint. 
     
     
         4 . The apparatus of  claim 1 , wherein a connection layout of the chip matches a connection layout of the second surface of the first PCB. 
     
     
         5 . The apparatus of  claim 1 , the first PCB comprising a second chip secured to the first PCB via a third solder joint at a third electrical contact on the first surface of the first PCB, wherein a melting temperature of the third solder joint is higher than the melting temperature of the second solder joint. 
     
     
         6 . An apparatus comprising:
 a first printed circuit board (PCB);   a component soldered to the first PCB via a first solder; and   a second PCB soldered to the first PCB via a second solder, wherein a melting temperature of the first solder is higher than a melting temperature of the second solder.   
     
     
         7 . The apparatus of  claim 6  comprising a spacer between the first PCB and the second PCB. 
     
     
         8 . The apparatus of  claim 6 , wherein the component includes a socket to receive a chip. 
     
     
         9 . The apparatus of  claim 6 , the second PCB comprising a heater trace to heat the second solder to the melting temperature of the second solder. 
     
     
         10 . The apparatus of  claim 6 , wherein the component includes a processor, and the second PCB includes a motherboard. 
     
     
         11 . A method comprising:
 soldering a chip to a first printed circuit board (PCB) using a first solder; and   soldering the first PCB to a second PCB using a second solder, a melting temperature of the first solder being higher than a melting temperature of the second solder.   
     
     
         12 . The method of  claim 11  comprising:
 heating the second solder to or above the melting temperature of the second solder, to melt the second solder; and 
 removing the first PCB from the second PCB, wherein the chip remains soldered to the first PCB. 
 
     
     
         13 . The method of  claim 12  comprising soldering a third PCB to the second PCB using a third solder, the third PCB comprising a second chip soldered using a fourth solder, a melting temperature of the fourth solder being higher than a melting temperature of the third solder. 
     
     
         14 . The method of  claim 13 , wherein the second chip is pin-incompatible with the first chip. 
     
     
         15 . The method of  claim 11 , wherein the chip comprises a processor socket, the chip is coupled to the processor socket, and the soldering a chip to the first PCB includes soldering the processor socket to the first PCB.